llvm-6502/lib/Target/Mips/MipsInstrInfo.cpp
Jakob Stoklund Olesen 78e6e00922 Remove the isMoveInstr() hook.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108567 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-16 22:35:46 +00:00

523 lines
17 KiB
C++

//===- MipsInstrInfo.cpp - Mips Instruction Information ---------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the Mips implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "MipsInstrInfo.h"
#include "MipsTargetMachine.h"
#include "MipsMachineFunction.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/Support/ErrorHandling.h"
#include "MipsGenInstrInfo.inc"
using namespace llvm;
MipsInstrInfo::MipsInstrInfo(MipsTargetMachine &tm)
: TargetInstrInfoImpl(MipsInsts, array_lengthof(MipsInsts)),
TM(tm), RI(*TM.getSubtargetImpl(), *this) {}
static bool isZeroImm(const MachineOperand &op) {
return op.isImm() && op.getImm() == 0;
}
/// isLoadFromStackSlot - If the specified machine instruction is a direct
/// load from a stack slot, return the virtual or physical register number of
/// the destination along with the FrameIndex of the loaded stack slot. If
/// not, return 0. This predicate must return 0 if the instruction has
/// any side effects other than loading from the stack slot.
unsigned MipsInstrInfo::
isLoadFromStackSlot(const MachineInstr *MI, int &FrameIndex) const
{
if ((MI->getOpcode() == Mips::LW) || (MI->getOpcode() == Mips::LWC1) ||
(MI->getOpcode() == Mips::LDC1)) {
if ((MI->getOperand(2).isFI()) && // is a stack slot
(MI->getOperand(1).isImm()) && // the imm is zero
(isZeroImm(MI->getOperand(1)))) {
FrameIndex = MI->getOperand(2).getIndex();
return MI->getOperand(0).getReg();
}
}
return 0;
}
/// isStoreToStackSlot - If the specified machine instruction is a direct
/// store to a stack slot, return the virtual or physical register number of
/// the source reg along with the FrameIndex of the loaded stack slot. If
/// not, return 0. This predicate must return 0 if the instruction has
/// any side effects other than storing to the stack slot.
unsigned MipsInstrInfo::
isStoreToStackSlot(const MachineInstr *MI, int &FrameIndex) const
{
if ((MI->getOpcode() == Mips::SW) || (MI->getOpcode() == Mips::SWC1) ||
(MI->getOpcode() == Mips::SDC1)) {
if ((MI->getOperand(2).isFI()) && // is a stack slot
(MI->getOperand(1).isImm()) && // the imm is zero
(isZeroImm(MI->getOperand(1)))) {
FrameIndex = MI->getOperand(2).getIndex();
return MI->getOperand(0).getReg();
}
}
return 0;
}
/// insertNoop - If data hazard condition is found insert the target nop
/// instruction.
void MipsInstrInfo::
insertNoop(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI) const
{
DebugLoc DL;
BuildMI(MBB, MI, DL, get(Mips::NOP));
}
void MipsInstrInfo::
copyPhysReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I, DebugLoc DL,
unsigned DestReg, unsigned SrcReg,
bool KillSrc) const {
bool DestCPU = Mips::CPURegsRegClass.contains(DestReg);
bool SrcCPU = Mips::CPURegsRegClass.contains(SrcReg);
// CPU-CPU is the most common.
if (DestCPU && SrcCPU) {
BuildMI(MBB, I, DL, get(Mips::ADDu), DestReg).addReg(Mips::ZERO)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
// Copy to CPU from other registers.
if (DestCPU) {
if (Mips::CCRRegClass.contains(SrcReg))
BuildMI(MBB, I, DL, get(Mips::CFC1), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
else if (Mips::FGR32RegClass.contains(SrcReg))
BuildMI(MBB, I, DL, get(Mips::MFC1), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
else if (SrcReg == Mips::HI)
BuildMI(MBB, I, DL, get(Mips::MFHI), DestReg);
else if (SrcReg == Mips::LO)
BuildMI(MBB, I, DL, get(Mips::MFLO), DestReg);
else
llvm_unreachable("Copy to CPU from invalid register");
return;
}
// Copy to other registers from CPU.
if (SrcCPU) {
if (Mips::CCRRegClass.contains(DestReg))
BuildMI(MBB, I, DL, get(Mips::CTC1), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
else if (Mips::FGR32RegClass.contains(DestReg))
BuildMI(MBB, I, DL, get(Mips::MTC1), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
else if (DestReg == Mips::HI)
BuildMI(MBB, I, DL, get(Mips::MTHI))
.addReg(SrcReg, getKillRegState(KillSrc));
else if (DestReg == Mips::LO)
BuildMI(MBB, I, DL, get(Mips::MTLO))
.addReg(SrcReg, getKillRegState(KillSrc));
else
llvm_unreachable("Copy from CPU to invalid register");
return;
}
if (Mips::FGR32RegClass.contains(DestReg, SrcReg)) {
BuildMI(MBB, I, DL, get(Mips::FMOV_S32), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
if (Mips::AFGR64RegClass.contains(DestReg, SrcReg)) {
BuildMI(MBB, I, DL, get(Mips::FMOV_D32), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
if (Mips::CCRRegClass.contains(DestReg, SrcReg)) {
BuildMI(MBB, I, DL, get(Mips::MOVCCRToCCR), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
llvm_unreachable("Cannot copy registers");
}
void MipsInstrInfo::
storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned SrcReg, bool isKill, int FI,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) const {
DebugLoc DL;
if (I != MBB.end()) DL = I->getDebugLoc();
if (RC == Mips::CPURegsRegisterClass)
BuildMI(MBB, I, DL, get(Mips::SW)).addReg(SrcReg, getKillRegState(isKill))
.addImm(0).addFrameIndex(FI);
else if (RC == Mips::FGR32RegisterClass)
BuildMI(MBB, I, DL, get(Mips::SWC1)).addReg(SrcReg, getKillRegState(isKill))
.addImm(0).addFrameIndex(FI);
else if (RC == Mips::AFGR64RegisterClass) {
if (!TM.getSubtarget<MipsSubtarget>().isMips1()) {
BuildMI(MBB, I, DL, get(Mips::SDC1))
.addReg(SrcReg, getKillRegState(isKill))
.addImm(0).addFrameIndex(FI);
} else {
const TargetRegisterInfo *TRI =
MBB.getParent()->getTarget().getRegisterInfo();
const unsigned *SubSet = TRI->getSubRegisters(SrcReg);
BuildMI(MBB, I, DL, get(Mips::SWC1))
.addReg(SubSet[0], getKillRegState(isKill))
.addImm(0).addFrameIndex(FI);
BuildMI(MBB, I, DL, get(Mips::SWC1))
.addReg(SubSet[1], getKillRegState(isKill))
.addImm(4).addFrameIndex(FI);
}
} else
llvm_unreachable("Register class not handled!");
}
void MipsInstrInfo::
loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned DestReg, int FI,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) const
{
DebugLoc DL;
if (I != MBB.end()) DL = I->getDebugLoc();
if (RC == Mips::CPURegsRegisterClass)
BuildMI(MBB, I, DL, get(Mips::LW), DestReg).addImm(0).addFrameIndex(FI);
else if (RC == Mips::FGR32RegisterClass)
BuildMI(MBB, I, DL, get(Mips::LWC1), DestReg).addImm(0).addFrameIndex(FI);
else if (RC == Mips::AFGR64RegisterClass) {
if (!TM.getSubtarget<MipsSubtarget>().isMips1()) {
BuildMI(MBB, I, DL, get(Mips::LDC1), DestReg).addImm(0).addFrameIndex(FI);
} else {
const TargetRegisterInfo *TRI =
MBB.getParent()->getTarget().getRegisterInfo();
const unsigned *SubSet = TRI->getSubRegisters(DestReg);
BuildMI(MBB, I, DL, get(Mips::LWC1), SubSet[0])
.addImm(0).addFrameIndex(FI);
BuildMI(MBB, I, DL, get(Mips::LWC1), SubSet[1])
.addImm(4).addFrameIndex(FI);
}
} else
llvm_unreachable("Register class not handled!");
}
//===----------------------------------------------------------------------===//
// Branch Analysis
//===----------------------------------------------------------------------===//
/// GetCondFromBranchOpc - Return the Mips CC that matches
/// the correspondent Branch instruction opcode.
static Mips::CondCode GetCondFromBranchOpc(unsigned BrOpc)
{
switch (BrOpc) {
default: return Mips::COND_INVALID;
case Mips::BEQ : return Mips::COND_E;
case Mips::BNE : return Mips::COND_NE;
case Mips::BGTZ : return Mips::COND_GZ;
case Mips::BGEZ : return Mips::COND_GEZ;
case Mips::BLTZ : return Mips::COND_LZ;
case Mips::BLEZ : return Mips::COND_LEZ;
// We dont do fp branch analysis yet!
case Mips::BC1T :
case Mips::BC1F : return Mips::COND_INVALID;
}
}
/// GetCondBranchFromCond - Return the Branch instruction
/// opcode that matches the cc.
unsigned Mips::GetCondBranchFromCond(Mips::CondCode CC)
{
switch (CC) {
default: llvm_unreachable("Illegal condition code!");
case Mips::COND_E : return Mips::BEQ;
case Mips::COND_NE : return Mips::BNE;
case Mips::COND_GZ : return Mips::BGTZ;
case Mips::COND_GEZ : return Mips::BGEZ;
case Mips::COND_LZ : return Mips::BLTZ;
case Mips::COND_LEZ : return Mips::BLEZ;
case Mips::FCOND_F:
case Mips::FCOND_UN:
case Mips::FCOND_EQ:
case Mips::FCOND_UEQ:
case Mips::FCOND_OLT:
case Mips::FCOND_ULT:
case Mips::FCOND_OLE:
case Mips::FCOND_ULE:
case Mips::FCOND_SF:
case Mips::FCOND_NGLE:
case Mips::FCOND_SEQ:
case Mips::FCOND_NGL:
case Mips::FCOND_LT:
case Mips::FCOND_NGE:
case Mips::FCOND_LE:
case Mips::FCOND_NGT: return Mips::BC1T;
case Mips::FCOND_T:
case Mips::FCOND_OR:
case Mips::FCOND_NEQ:
case Mips::FCOND_OGL:
case Mips::FCOND_UGE:
case Mips::FCOND_OGE:
case Mips::FCOND_UGT:
case Mips::FCOND_OGT:
case Mips::FCOND_ST:
case Mips::FCOND_GLE:
case Mips::FCOND_SNE:
case Mips::FCOND_GL:
case Mips::FCOND_NLT:
case Mips::FCOND_GE:
case Mips::FCOND_NLE:
case Mips::FCOND_GT: return Mips::BC1F;
}
}
/// GetOppositeBranchCondition - Return the inverse of the specified
/// condition, e.g. turning COND_E to COND_NE.
Mips::CondCode Mips::GetOppositeBranchCondition(Mips::CondCode CC)
{
switch (CC) {
default: llvm_unreachable("Illegal condition code!");
case Mips::COND_E : return Mips::COND_NE;
case Mips::COND_NE : return Mips::COND_E;
case Mips::COND_GZ : return Mips::COND_LEZ;
case Mips::COND_GEZ : return Mips::COND_LZ;
case Mips::COND_LZ : return Mips::COND_GEZ;
case Mips::COND_LEZ : return Mips::COND_GZ;
case Mips::FCOND_F : return Mips::FCOND_T;
case Mips::FCOND_UN : return Mips::FCOND_OR;
case Mips::FCOND_EQ : return Mips::FCOND_NEQ;
case Mips::FCOND_UEQ: return Mips::FCOND_OGL;
case Mips::FCOND_OLT: return Mips::FCOND_UGE;
case Mips::FCOND_ULT: return Mips::FCOND_OGE;
case Mips::FCOND_OLE: return Mips::FCOND_UGT;
case Mips::FCOND_ULE: return Mips::FCOND_OGT;
case Mips::FCOND_SF: return Mips::FCOND_ST;
case Mips::FCOND_NGLE:return Mips::FCOND_GLE;
case Mips::FCOND_SEQ: return Mips::FCOND_SNE;
case Mips::FCOND_NGL: return Mips::FCOND_GL;
case Mips::FCOND_LT: return Mips::FCOND_NLT;
case Mips::FCOND_NGE: return Mips::FCOND_GE;
case Mips::FCOND_LE: return Mips::FCOND_NLE;
case Mips::FCOND_NGT: return Mips::FCOND_GT;
}
}
bool MipsInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
MachineBasicBlock *&TBB,
MachineBasicBlock *&FBB,
SmallVectorImpl<MachineOperand> &Cond,
bool AllowModify) const
{
// If the block has no terminators, it just falls into the block after it.
MachineBasicBlock::iterator I = MBB.end();
if (I == MBB.begin())
return false;
--I;
while (I->isDebugValue()) {
if (I == MBB.begin())
return false;
--I;
}
if (!isUnpredicatedTerminator(I))
return false;
// Get the last instruction in the block.
MachineInstr *LastInst = I;
// If there is only one terminator instruction, process it.
unsigned LastOpc = LastInst->getOpcode();
if (I == MBB.begin() || !isUnpredicatedTerminator(--I)) {
if (!LastInst->getDesc().isBranch())
return true;
// Unconditional branch
if (LastOpc == Mips::J) {
TBB = LastInst->getOperand(0).getMBB();
return false;
}
Mips::CondCode BranchCode = GetCondFromBranchOpc(LastInst->getOpcode());
if (BranchCode == Mips::COND_INVALID)
return true; // Can't handle indirect branch.
// Conditional branch
// Block ends with fall-through condbranch.
if (LastOpc != Mips::COND_INVALID) {
int LastNumOp = LastInst->getNumOperands();
TBB = LastInst->getOperand(LastNumOp-1).getMBB();
Cond.push_back(MachineOperand::CreateImm(BranchCode));
for (int i=0; i<LastNumOp-1; i++) {
Cond.push_back(LastInst->getOperand(i));
}
return false;
}
}
// Get the instruction before it if it is a terminator.
MachineInstr *SecondLastInst = I;
// If there are three terminators, we don't know what sort of block this is.
if (SecondLastInst && I != MBB.begin() && isUnpredicatedTerminator(--I))
return true;
// If the block ends with Mips::J and a Mips::BNE/Mips::BEQ, handle it.
unsigned SecondLastOpc = SecondLastInst->getOpcode();
Mips::CondCode BranchCode = GetCondFromBranchOpc(SecondLastOpc);
if (BranchCode != Mips::COND_INVALID && LastOpc == Mips::J) {
int SecondNumOp = SecondLastInst->getNumOperands();
TBB = SecondLastInst->getOperand(SecondNumOp-1).getMBB();
Cond.push_back(MachineOperand::CreateImm(BranchCode));
for (int i=0; i<SecondNumOp-1; i++) {
Cond.push_back(SecondLastInst->getOperand(i));
}
FBB = LastInst->getOperand(0).getMBB();
return false;
}
// If the block ends with two unconditional branches, handle it. The last
// one is not executed, so remove it.
if ((SecondLastOpc == Mips::J) && (LastOpc == Mips::J)) {
TBB = SecondLastInst->getOperand(0).getMBB();
I = LastInst;
if (AllowModify)
I->eraseFromParent();
return false;
}
// Otherwise, can't handle this.
return true;
}
unsigned MipsInstrInfo::
InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
MachineBasicBlock *FBB,
const SmallVectorImpl<MachineOperand> &Cond,
DebugLoc DL) const {
// Shouldn't be a fall through.
assert(TBB && "InsertBranch must not be told to insert a fallthrough");
assert((Cond.size() == 3 || Cond.size() == 2 || Cond.size() == 0) &&
"Mips branch conditions can have two|three components!");
if (FBB == 0) { // One way branch.
if (Cond.empty()) {
// Unconditional branch?
BuildMI(&MBB, DL, get(Mips::J)).addMBB(TBB);
} else {
// Conditional branch.
unsigned Opc = GetCondBranchFromCond((Mips::CondCode)Cond[0].getImm());
const TargetInstrDesc &TID = get(Opc);
if (TID.getNumOperands() == 3)
BuildMI(&MBB, DL, TID).addReg(Cond[1].getReg())
.addReg(Cond[2].getReg())
.addMBB(TBB);
else
BuildMI(&MBB, DL, TID).addReg(Cond[1].getReg())
.addMBB(TBB);
}
return 1;
}
// Two-way Conditional branch.
unsigned Opc = GetCondBranchFromCond((Mips::CondCode)Cond[0].getImm());
const TargetInstrDesc &TID = get(Opc);
if (TID.getNumOperands() == 3)
BuildMI(&MBB, DL, TID).addReg(Cond[1].getReg()).addReg(Cond[2].getReg())
.addMBB(TBB);
else
BuildMI(&MBB, DL, TID).addReg(Cond[1].getReg()).addMBB(TBB);
BuildMI(&MBB, DL, get(Mips::J)).addMBB(FBB);
return 2;
}
unsigned MipsInstrInfo::
RemoveBranch(MachineBasicBlock &MBB) const
{
MachineBasicBlock::iterator I = MBB.end();
if (I == MBB.begin()) return 0;
--I;
while (I->isDebugValue()) {
if (I == MBB.begin())
return 0;
--I;
}
if (I->getOpcode() != Mips::J &&
GetCondFromBranchOpc(I->getOpcode()) == Mips::COND_INVALID)
return 0;
// Remove the branch.
I->eraseFromParent();
I = MBB.end();
if (I == MBB.begin()) return 1;
--I;
if (GetCondFromBranchOpc(I->getOpcode()) == Mips::COND_INVALID)
return 1;
// Remove the branch.
I->eraseFromParent();
return 2;
}
/// ReverseBranchCondition - Return the inverse opcode of the
/// specified Branch instruction.
bool MipsInstrInfo::
ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const
{
assert( (Cond.size() == 3 || Cond.size() == 2) &&
"Invalid Mips branch condition!");
Cond[0].setImm(GetOppositeBranchCondition((Mips::CondCode)Cond[0].getImm()));
return false;
}
/// getGlobalBaseReg - Return a virtual register initialized with the
/// the global base register value. Output instructions required to
/// initialize the register in the function entry block, if necessary.
///
unsigned MipsInstrInfo::getGlobalBaseReg(MachineFunction *MF) const {
MipsFunctionInfo *MipsFI = MF->getInfo<MipsFunctionInfo>();
unsigned GlobalBaseReg = MipsFI->getGlobalBaseReg();
if (GlobalBaseReg != 0)
return GlobalBaseReg;
// Insert the set of GlobalBaseReg into the first MBB of the function
MachineBasicBlock &FirstMBB = MF->front();
MachineBasicBlock::iterator MBBI = FirstMBB.begin();
MachineRegisterInfo &RegInfo = MF->getRegInfo();
const TargetInstrInfo *TII = MF->getTarget().getInstrInfo();
GlobalBaseReg = RegInfo.createVirtualRegister(Mips::CPURegsRegisterClass);
BuildMI(FirstMBB, MBBI, DebugLoc(), TII->get(TargetOpcode::COPY),
GlobalBaseReg).addReg(Mips::GP);
RegInfo.addLiveIn(Mips::GP);
MipsFI->setGlobalBaseReg(GlobalBaseReg);
return GlobalBaseReg;
}